Phototypographical machine



Feb. 2, 1960 v CQRRADO r 2,923,212

PHOTOTYPOGRAPHZICAL MACHINE 8 Sheets-Sheet 1 Filed Nov. 25. 1956INVENTORS VICTOR M. Com/100 y RICHARD/f. WALKER jg 6 7 ATTORNEYS 2, 1950v. M. CORRADO ETAL 2,923,212

PHOTOTYFOGRAPHICAL MACHINE 8 Sheets-Sheet 2 Filed Nov. 23, 1956INVENTORS R m A ZL RW /R 0 x 0 C H MD W M wwfly CM 4 WR B 1960 v. M.CORRADO ET AL 2,923,212

PHOTOTYPOGRAPHICAL MACHINE 8 Sheets-Sheet 3 Filed Nov. 25. 1956INVENTORS VICTOR M. CORRADO BY R/c/m/w K. WALKER ATTORNEYS b 1960 v. M.CORRADO ETAL 2,923,212

PHOTOTYPOGRAPHICAL MACHINE Filed Nov. 23. 1956 8 Sheets-Sheet 4 --/52133 H 155- 150 I l INVENTORS VICTOR M. COR/M00 5 BY RICHARD K. WA KER )5%av ATTORNEYS Feb. 2, 1960 v. M. CORRADO ETAL 2,923,212PHOTOTYPOGRAPHICAL MACHINE Filed Nov. 25, 1956 8 Sheets-Sheet 5 IN VEN T0R8 VICTOR M. 601M400 BY RIC/MRO K. W LKtR TORNEYS Feb. 2, 1960 v. M.CORRADO ETAL PHOTOTYPOGRAPHICAL MACHINE 8 Sheets-Sheet 6' Filed Nov. 23.1956 wwwiku M R wmMw mm? M &5? mw m T 1mm W A 0 "$1 WR 1960 v. M.CORRADO ETAL 2,923,212

PHOTOTYPOGRAPHICAL momma 8 Sheets-She et 7 Filed Nov. 23, 1956 R 0 f 5fi 3 M m M w vm WM m D RM w 0 TH M K Wk V. B

1950 v. M. CORRADO ETAL PHOTOTYPOGRAPHICAL MACHINE Filed Nov. 23. 1956 8Sheets-Sheet 8 w 101/ 2 Z PHOTOFLASH a 03 5011 CONTROL J 61-M y!-C/Rcu/TRY dl .i

k Jifirw r wv trt r5? Z00 THYRATRON ARMATURE 1.97 I97 197 197 m, CONTROLCIRCUITRY 200 1767;

Li 1 i I i i I i 1 f INVENTORS f? VICTOR/4. comma BY RICHARD A.

KER

aa-mpa ATTORNEYS 2,923,212 PHOTOTYPOGRAPHICAL MACHINE Victor M. Corrado,Williston Park, N.Y., and Richard K.

Walker, Convent, N J., assignors to Mergenthaler Linotype Company, acorporation of New York Application November 23, 1956, Serial No.624,136 17 Claims. (Cl. 95-45) This invention relates to a tape operatedphototypographical machine of the general organization disclosed in US.applications Serial No. 354,826, filed March 13, 1953, Serial No.419,012, filed March 26, 1954, and Serial No. 432,757, filed May 27,1954, wherein transverse type lines are photographed one after anotherin spaced relation on a strip of sensitized fihn or paper as the latteris advanced endwise through the machine in step-by-step fashion.

In a machine of the type therein disclosed, a font plate having an arrayof transparent characters which vary in set widths on a unit basis isinterposed between a source of light and a shutter mechanism whichserves to selectively expose the various characters. In operation, theshutter mechanism is actuated to expose a character selected to bephotographed and the light source is then rendered operative to projectlight through the character -to a lenslet individual to the character.The lenslet forms the light which passestherethrough into a bundle ofcollimated rays and these impinge on an imaging lens common to all thelenslets. The imaging lens, in turn,

serves to form, in space and on its optical axis, an image of theselected character. A point size changing lens system is providedcomprising two eye piece lenses whose combined function is to vary thesize or magnification of the selected character as it is finallyrecorded on the sensitized film or paper. The eye piece lenses alsoserve to transmit the light forming the image in space as a bundle ofcollimated light rays to a mirror carried by a carriage thatcontinuously traverses the sensitized film during the composition of aline, the film remaining stationary during composition. The mirrordeflects the bundle of light rays at an angle of 90 and directs it to afurther lens system which is also mounted on the moving carriage andwhich serves to decollimate the light rays and project them onto thestationary light sensitive film to form an image of the selectedcharacter in a point size controlled by the setting of the eye piecelenses.

The operation of the machine is controlled by means of a coded tape.Each character to be photographed is represented on the'tape by a codesignal which may be thought of as comprising two portions, one of whichidentifies the character and controls the operation of the shuttermechanism to selectively expose the character to be photographed, andthe other portion of which represents the unit set width of thecharacter and is transmitted to an electronic counter. A transparentgrid plate, having a row of opaque lines spaced apart in units of an cmof the point size of the photographed characters, is secured to thecarriage for movement therewith and traverses a light beam extendingfrom a light source to a photocell in such a manner as to interrupt thelight beam once for each unit of an em travelled by the carriage. Theresulting pulses from the photocell are transmitted to the electroniccounter. When the number of pulses from the photocell correspond withthe numerical value of the unit width of the character transmitted tothe countor by the code signal on the tape, the counter generates nitedt es P e t an output pulse which momentarily flashes the source of lightbehind the font plate to thus photograph the selected character onto thelight sensitive film. When it is desired to change the size ormagnification of the repro duced character from one point size toanother, the positions of the two eye piece lenses must be changed withrespect to one another and to the large imaging lens; the relativepositions of the grid plate must be changed to bring into operativeposition with respect to the photocell unit another row of opaque linesgraduated in units of an em of the new point size of the photographedcharacters; and the intensity of the light must be adjusted so thatregardless of the point size of the photographed characters the filmwill be exposed to the same amount of light.

While, in general, the photocomposing machine of the aforementionedapplications is satisfactory, it is to be noted that the above changesmust be made manually, with a consequent loss of time in operation. Alsoin said machine, when the size of the photographed characters isincreased beyond the smallest size it is capable of reproducing, thenumber of reproductions created during a given composing period isdecreased, this being due to the fact that since the spacing between thelines on the grid plate increases as the size of the reproduced characters is increased, the time between successive flashings of the lamp isincreased accordingly.

In accordance with the present invention the changes in the positions ofthe eye piece lenses and of the grid plate according to point size ofthe characters to be photographed, as well as the variation in lightintensity to correspond, are all made automatically by means responsiveto the decoding of an appropriate signal on the control tape. Inaddition, there are also provided means responsive to the decoding ofthe same tape signal for adjusting the speed at which the projectionlens carriage, and consequently, the grid plate, travels past thephotocell so that the same time interval is required to flash the lampfor any given character regardless of its point size. It is thus insuredthat the speed of photographic composition remains constant regardlessof the point size of the photographed characters.

In the drawings:

Fig. 1 is a front elevation of a phototypographical machine equippedWith the present invention;

Fig. 2 is a sectional view taken-along line 22 of Fig. 1;

Fig. 3 is a side elevation, with parts broken away, of the mechanismshown in Fig. 2;

Fig. 4 is a plan view of the detent mechanism used for fixing theposition of one lens carriage;

Fig. 5 is a sectional view taken along line 5-5 of Fig. 1;

Fig. 6 is a side elevation, with parts broken away, of the mechanismshown in Fig. 5;

Fig. 7 is a front elevation of the grid plate or unit measuring device;

Fig. 7A is a sectional view taken along line 7A-7A of Fig. 7;

Fig. 8 is a sectional view taken along line 8-8 of Fig. 7;

Fig. 9 is a sectional view taken along line 9-9 of Fig. 1;

Fig. 10 is an elevational view of the braking mechanism for arrestingcarriage motion;

Fig. 11 is a segmental elevational view, with parts; broken away,showing the carriage drive mechanism;

Fig. 12 is a schematic electrical circuit diagram show-- ing the pointsize selecting circuit;

Fig; 13 is a schematic electrical circuit diagram show ing the controlcircuit for the lens carriage motor;

Fig. 16 is a schematic electrical circuit diagram showing the carriagedrive motor speed control circuit.

In Fig. v 1 there is shown a photocomprosing machine similar to theone'disclosed in the aforementioned application Serial No. 419,012 butmore specifically embodying the improvements of the present invention. Asource of lig'ht 20 is shown mounted within housing 21, as is reflector22 which serves to concentrate and intensify the light energy in adirection forward of the source. The

light is then distributed relatively evenly over the area of a fontplate 23'by a condensing lens system 24, the font plate having an entirearray of transparent characters arranged thereon against an opaquebackground.

A shutter mechanism '25 is next provided whereby the light passingthrough a single character selected for reproduction will be transmittedto succeeding machine components. Located forward of the shuttermechanism, within housing 30, is a lenslet array 26 which'includes anindividual lenslet for each character of the font. The lenslet and thefont plate are disposed relative to each other such that light passingthrough a selected character is collimated by the associated lenslet. Asingle imaging lens 27, common to all of the lenslet of array 26, isprovided within the housing 30, the lens 27 serving to form an image, inspace and on its optical axis, of a selected character. The position ofthe image along the optical axis is determined by the location of an eyepiece objective lens 31; The light transmitted through the lens 31 isnext collimated by a second eye piece lens 3'2 and thereafter reflectedby mirror 33 to projection lens system 34 which reimages the characteron a sensitized film 35 provided in film magazine 36. The mirror 33 andlens system 3=4,'as well as a filter element at are located within ahousing 37 supported by a carriage 41 which is mounted for reciprocatorymotion before the sensitized film. A grid plate 42, for measuring theextent of carriage movement, is provided and will be more specificallydescribed hereinafter.

A pair of horizontally disposed, parallel, spaced apart guide rods 43and 44 are supported in brackets 45 and 46 mounted on the bed plate 47of the machine (Figs. 2

and The rods serve as a guiding support for eye piece objective lens 31,which is secured in holder 50, and also for the second eye piece lens32, which is secured in holder 51. Both of these lens holders areslidable along the guide rods, in a manner to be hereinafter described,for the purpose of controlling the point size of the images recorded onthe sensitized film.

The projection lens carriage 41 is also supported on the guide rods 43and 44 (Fig. 7). A motor '52 is provided to drive the carriage throughthe intermediary of spur gears 53 and 54 and lead screw 55 formed on theshaft 56 supporting gear 54 (Fig. 11).

Referring now to Fig. 5, the eye piece objective lens holder '50 is seento be mounted on a cross plate 57 extending between sleeve members 60and 61 slidable on guide rods 43 and 44, respectively. A horizontal web62, projecting rearwardly from sleeve 69, serves to support rack 63which is secured thereto by screws (4. The rack is engaged by a pinion6'5 keyed to the shaft 66 of reversing motor 67, the shaft beingsupported at its forward end by an angle bracket "74). The motor andbracket '70 are mounted on a plate 71 carried by a pair of anglebrackets 72 secured to the bedplate of the machine (Fig. l).

A spur gear 73, keyed to motor shaft 66, drives a large gear 74 (whichextends through a slot in plate 11) to rotate a fore-and-aft shaft 75 towhich it is keyed. The shaft 75 is rotatably supported in pillow blocks'76 depending from th underside of plate 71 and serves to actuatecommutator mechanism 77 consequent upon rotation of motor 67. Thecommutator is mounted in housing 80 and 'will'be described more,specifically hereinafter whenv be noted that direction oflens travel,i.e., direction of motor rotation, and the extent thereof will becontrolled by the commutator mechanism. A bevel gear 81 is provided onthe forward end of shaft 75 to rotate pinion 82 for a purpose which,again, will be later considered.

A vertically disposed detent plate 83, having a plurality of detents 34along its top edge, is fastened to a lug 85 projecting forwardly fromthe front side of sleeve 60, as by screws 86 (Figs. 5 and 6). A roller87 for engaging a detent is rotatably mounted on the extremity of alever '96, which is pivotally attached to the angle bracket 91 risingfrom plate 71. A tension spring 92 biasesthe lever and roller 87 todetent engaging position.

The second eye piece lens holder '51 is shown mounted on a cross plate33 (Figs. 2 and 3) extending between sleeve members 94 and 95 alsoslidably arranged on guide rods 43 and 44, respectively. A downwardlyprojecting rack 9=6is fastened, by means of screws 97, to a block 1tl0formed integral with sleeve95. On operative engagement with the rack 96is a pinion 101 keyed to the shaft 102 of motor 103, the shaft beingsupported-by angle brackets 1ti4and105 secured to plate 71. Also keyedto shaft 102 is spur gear 106 which engages a gear 107 keyed to afore-and-aft shaft 110 rotatably supported in pilow blocks 111. Acommutator mechanism 112, shownin housing 113, will be consideredhereinafter when the wiring. diagram is described. Similar in functionto eye piece objective lens commutator mechanism 77, the presentcommutator mechanism 11-2 controls the direction and extent of thesecond eye piece lens 32 when the lens is being repositioned to providecharacter reproduction of a different point size.

A detent mechanism, including a horizontally disposed detent plate 114secured to sleeve 95 through the intermediary of angle member 115 isprovided to lock the lens supporting apparatus in its adjusted position'(Fig. 4). A pin 116, projecting vertically from one arm of ahorizontally disposed bell crank 117, is urged into 'engagement with thedetent edge of plate 114 by a tension spring extending between a fixedlymounted pin 121 and a depending pin 122 of the bell crank. The bellcrank and its associated mechanism are mounted on'plate' 123 which, inturn, is secured to plate 71.

The pinion 82, driven by bevel gear 81, is carried at one end of shaft124 journaled in member 125, while the remote end of the shaft isconnected to an obliquely dis} posed drive shaft 126 through a universalcoupling 127 (see Figs. 1 and 7). At the lower end of shaft 126, asecond universal coupling 130 is provided whereby a shaft 131 isdriven.Shaft 131 is journaled for rotative movement in the spaced apartblocks'132 of a channel shaped member 133 provided below the bedplate 47of the machine. a A pair of 'pinions 134 are keyed to shaft 131 forrotation therewith. The edges 135 of member 133 are themselves channelshaped in that longitudinal grooves'136 are formed therein to serve asguideways for two vertically movableracks 137 which cooperate withpinions 134 (Fig. 7A). The racks are joined at their per ends by acrosspiece 140, thus providing a unitary structure capableof areciprocatory motion in a vertical direction under the influence 'of thedrive shaft 126.

. The rear surface of the'cross-piece 140 has a groove of channel 141formed therein. A roller 142, rotatably sup ported in the lower righthand corner of the grid plate" frame 143, projectsinto and rides on thelower surface of channel141. A frame 143 also is provided with a" units.an em jot the; different "point sizes finwhich:

- shown in Fig. 10. Intermediate photocomposing machine will photographcharacters. Of course, the spacing between collars 146 and the length ofrod 147 is such as to permit the grid plate frame to be translated in avertical direction a distance sufiicient to bring either the uppermostor lowermost row of markings on the grid plate into alignment with thephotocell unit 150. As shown in Fig. 8, the photocell unit comprisessimply a source of light 151 and a light responsive element 152 bothfixedly mounted on the machine bedplate 47 to function as a fixedreference point past which the grid plate is carried by projection lenscarriage 41 as the latter is reciprocated during line composition.

It will be noted that the rows of markings on grid plate 42 are notequally spaced one from another as in the aforementioned application.Rather, the rows are spaced apart a distance dependent on the amount ofrotation of motor 67 required to properly position eye piece objectivelens 31 for the point size reproductions selected.

As heretofore stated, the speed of photographic composition ismaintained constant regardless of the point size of the photographedline of characters. Accordingly, the carriage 41, which causes theprojection lens to traverse the stationary sensitized film and the gridplate to traverse the photocell unit, is provided with a variable speeddrive. Referring to Figs. 9 and 11, the carriage is shown as being across-platform 153 extending between sleeves 154 and 155 slidablymounted on guide rods 43 and 44, respectively. As previously described,the guide rods are supported in brackets 45 and 46 mounted on thebedplate of the machine. Atop the carriage is housing 37 containing theprojection lens 34 and the 45 mirror 33 for deflecting the characterlight beams at right angles to the longitudinal axis of the machine,while to .one side of the carriage, the grid plate mechanism hereinabovedescribed is mounted. Depending from the under- "side of the carriage isan internally threaded block 156 which cooperates with the lead screw 55formed on shaft 56. The shaft 56 is journaled at one end in bearing 157provided in upright bracket 46 and at its extremity is provided with thespur gear 54 which is driven by the gear 53 mounted on shaft 160 ofmotor 52. The motor is a reversible A.C. motor of the variable speedtype in which speed changing is effected by control of the armaturecurrent. In the present apparatus, the speed control mechanism isresponsive to the decoding of the point size signal. The circuit foreffecting such control is shown in Fig. 16 and will be describedhereinafter. It will suffice, now, to note that as the point size rangeof the photographic composition is increased, the motor speed, and hencethe carriage speed, is similarly increased, while as the point size ofcomposition is decreased, the motor speed is decreased.

An electrically actuated mechanical brake is provided to arrest carriagemotion at the extremes of carriage travel or whenever else the carriagemotion may be halted after the motor 52 is deenergized, and this is gear54 and bearing 157, shaft 56 is provided with a brake disc 161 (Fig.11). Preferably the disk has a cork edge surface, although any suitablematerial may be utilized to achieve the proper braking action. A metalband 162 surrounds the disk and at its ends is connected to pivotinglevers 163 of a lazy tongs apparatus (Fig. A pivot pin 164 is secured tothe upright bracket 46 so that its position remains relatively fixed.The opposite ends of the levers 163 are connected to the swinging arm165 of a solenoid 166 by links 167 and 170, all the connectionstherebetween being pivotal. A tension spring 171 extends between levers163 to urge band 162 into clamping relation to the disk 161. To releasethe brake, solenoid 166 is energized to swing arm 165 counterclockwiseand thereby counteract the action of spring 171. A pair of stop pins 172limit the movement of levers 163 when the brake is released bysolenoid166. The brake is,

therefore, seen to be mechanically applied and electrically released toinsure a fail safe operation.

In addition to the machine adjustments above described, which all takeplace in response to a point size signal, it is now noted that theintensity of the light source 20 is also controlled in response to thepoint size signal. In the aforementioned patent application Serial No.419,012, the circuit for triggering the flash lamp light source isdescribed in detail and includes a group of capacitors which control theintensity of the light used in photographing the character images. It isthen noted that when the point size of the photographed characters is tobe varied, the value of the capacitor is likewise changed by manualmeans. In Figs. 14 and 15 is shown a circuit whereby the capacitorvalues in the flash lamp circuit are controlled by relay switching ofcapacitors into and out of the circuit. As the point size of thephotographed images increases, the light intensity must increase andconsequently the capacitor value is increased, as by connectingadditional capacitors in parallel. Conversely, as the point sizedecreases, the light requirements decrease and the capacitor value isdecreased, as by disconnecting capacitors from the circuit.

Referring to Fig. 12, when a point size signal in the control tape isdecoded by the tape reading mechanism, contacts XPSI engage; the relaycoil controlling the operation of the contacts not being shown. ContactsXPSl complete a circuit, through normally closed con- .tacts 173 and174, for point size switch coil PS, with the result that contacts PS1and PS2 engage. Contacts 173 are interlock contacts and will not bedescribed further. In the present description, it will be noted thatletter designations generally are applied to the coils ofelectromagnetic switches, and the same letter designations withreference numerals appended thereto are applied to contacts of the sameswitches. Contacts PS1 provide a self holding circuit for coil PS andcontacts PS2 complete a circuit for the energization of stepping switchcoil PSS through the stepper interrupter contacts P881 and contacts ST3.Immediately upon energization of coil PSS, contacts PSSI separate todeenergize the coil and advance brushes 175 175 etc. one position intoengagement with the next pair of contacts 176, 176 etc. Deenergizationof coil PSS causes contacts P881 to again engage, with the result thatcoil PSS is energized and contacts PSS1 separated thereby deenergizingcoil PSS; the brushes 175 etc. again advancing one position. Thestepping process is repeated until brushes 175 complete a circuitthrough the relay tree circuit 177 (the particular circuit beingdetermined in a well known manner by the point size signal decoded whichcontrols the operation of the contacts in the relay tree), one ofcontacts 176, brush 175 another one of contacts 176 normally closed.contact ST1, stopping relay coil ST and contacts PS2. Coil ST isenergized and contacts ST3 thereupon separate to interrupt the circuitfor stepping switch coil PSS. It is also noted that when, as nowassumed, the brushes are connected to the B-jwire through the relay treecircuit 177, stepping switch coil PSS is shorted .out through rectifier180 to prevent further advance of brushes 175*, etc.

Contacts ST1 separated and contacts ST2 engaged upon the energization ofcoil ST, the latter operation taking place prior to the former, so thata self-holding circuit for coil ST is provided prior to the interruptionof the circuit through the relay tree circuit 177. A 'With the arrest orstopping of the stepping switch operation in a position determined bythe particular point size signal, a brush 175 completes a circuitthrough contacts ST4 (engaged when coil ST was ener- 1 t'through segment183, then: relay coil i will -"be energized (contacts 184. having i beenpreviously energized by circuitry not shown'). The circuit is tracedfrom segme nt183 through the conductor 185 to ring 186 and brush 187.Energization of coil F will cause the motor 67-, for positioning the eyepiece objective lens holder 50 to rotatein a forward direction. On theother hand, if: the circuit is completed through segment 182, then relaycoil- R will be energized (contacts 190 being closed by circuitry aboveeluded to). This latter circuit is traced fromsegment 182 and throughpickup 191 and will causethe motor 67 to rotate in a reverse direction.

As motor 67 rotates to position the lens holder 50 in accordancewiththepoint size signaldecoded, commutator segments 182 and 183 rotateaboutthe stationary pi okup"191. Also, rotating brush 192 of the other partof-commutator77 sweeps over the stationary contacts 193 until a circuitis completed through the contacts connected to brush 175 brush 192, slipring 194 and brush 195 to energize motor stopping relay MS. When therelay is energized, the motor driving the lens carriage is deenergizedand the carriage will 'be positioned to control the point size of thephotographed images according to the point size signal decoded. Also,through 'drive shaft126, thegrid plate 42 will be positioned accordingto the point size signal decoded.

It is understood, of course, that a circuit similar to that shown in'Fig. 13 is provided to control the positioning oflens holder 51.Separate electrical apparatus is provided, inasmuch as the amount ofmovement required of each carriage difiers. In fact, under certain"circumstances, one carriage may move in one direction while the othercarriage may move in the opposite direction when changing the lenspositions from one point size setting to another.

- Reference is now made to Figs. 14 and 15, wherein the circuitryforcontrolling the intensity of the light flash is shown schematically.The contacts 176, 176 etc.

are simply additional contact layers on the point size stepper switchhereinbefore referred to, and brushes 175, 175 etc. coact therewith asshown particularly in Fig. 14 The at rest position of the-brushes isdetermined by the point size signal decoded and it corresponds to-theposition taken by brushes 175 and 175 in Figs. 12 and 13. Assuming thatthe point size signal results in the brushes taking the positionillustrated, then a circuit will be completed through contacts 176 which-remain engaged, except when the electrical equipment :is beingrepositioned, to provide for a different point size .contact 196 andbrush l75 for capacitor control relay coil 4CA. Consequently, contacts4CA1 engage (Fig. 15) and capacitor Q4 is connected into the photoflashcontrol circuitry, for the details of which see the aforementionedapplication Serial No. 419,012. Depending on the stopping position ofbrushes 175 175 etc.,

one or more of relays 1CA, ZCA, 30A and 4CA will be energized to causeone or more of capacitors Q1, Q2, Q3 and Q4 to be connected in parallelin the photoflash circuitry. For example, if brushes 175, etc. had beenstopped on the contacts two positions to the right of where they areshown, circuits would have been completed for the energization of coils10A, 3CA and 4CA,

capacity of the circuit. Under certain circumstances, as

when brushes 175 to 175 (Fig. 14) arein the first or seventh position,andno circuit is completed for relays {10A to-4CA, only capacitor Q5will be connected to thephototlash intensity circuit.

2-. 1x111 fig. lfi-there-is shown thQI'QSIStQI' switching circuit- "forthe thyrati-on; armature speedf control "circuitry a motor 52' whichbon'trolsflthe' composingor photographing s eed er the machine.Contacts; 176Fand 1 77 are, sir'nilarly fto contacts "176, "176, etc.,in'additional contact 'layers of thefpoint size' stepping switch.Brushes 175 and l 'arestepped as stepping switch coil PSS isenergizedand deener'gized as herei'nabove described. Contact's 176 are connectedto movable brushes'197, as

shown, which coact with the various resistors 2&0 to provide for anadjustable speed control.

The resistors increase in value from left to right in the drawing. Itwill be noted that the pair of brushes, in each of their positions,connectonly a single resistor to the thyratron circuit, and since theresistors increase in' value from'left to right, the motor sp'eeds willincrease as the brushes similarly move'fror n left to right. Therefore,as brushes 17'5 and move rightwardly, a larger point size isrepresented.

In this manner, a constant composing speed is effected regardless of thepoint size of the photographed images. The thyratron armaturecontrol-circuitry itself may be of the type commercially available formotor speed control.

Having thus described the invention, it is to be understood that manymodifications could be made to the above preferred arrangement forcarrying out the invention and many apparently widely differentembodiments thereof could be made without departingfromthe scopethereof,

and therefore, all matter contained in the above description or shown inthe accompanying drawings shallbe interpreted as illustrative and not ina limiting sense. For

instance, the point size changing lens assembly, inlieu of the tworelatively adjustable lenses 31 and 32, could comprise an adjustableplurality of sets of lenses, one set for each different point size, asshown in applicationSerial No. 354,826. Moreover, while the variousautomaticadjustments are herein shown as primarily electric,nevertheless in the broader aspects of the invention, they could beotherwise so long as they are subject to control of a point size codesignal.

It may be pointed out that the optical'system herein disclosed iscapable of cooperating with master font plates halving type charactersof different point size. Thus, it may be assumed that the typecharacters on the master font plate are either of 5 pt. size or of 10pt. size. Since the 10 pt. size is-a multiple of the 5 pt. size, bothsizes of master characters will be magnified in the same ratio by thesame adjustment of the eye piece lenses 31 and 32. The other elements ofthe machine may be preset to correspond to the font plate in use.

What is claimed is:

. 1. In a coded tape operated 'phototypographical machine equipped witha font plate presenting an array of transparent type characters of agiven point size and 'which vary in set widths on a unit basis, a lamppositioned adjacent said plate and adapted when flashed to project lightthrough a selected character to an optical system which includes anadjustable point size changing lens assembly for photographing saidselected character on a light sensitive member of a differentpredetermined point size, means for producing relative movement betweenthe light sensitive memberand said optical system for line composition,and an adjustable unit measuring device for measuringeach unit distanceof travel of the line composing movement and controlled in its operationby such movement, said unitmeasuring device. being adapted to v flashsaid lamp theinstant the relative movement bea tween the light sensitivemember and the optical system equals the setwidth of saidcharacter, andsaid unit measuring devicehavinga plurality of rows ofpulse generatingmarkings which control the flash of the lamp, there being as many rowsof such markings. as there are different point sizes,and said'markingsbeing spaced apart at different distances in the respective rows, thecombine} tioii'of rneans'responsivet o a'code signalon the operatingtape for adjust-ing said lens assembly according" to the point size-0fthecharacterto be photographe'dand for simultaneously adjusting saidunit measuring deviceto bring into operative position the correspondingrow of pulse generating markings to flash said lamp the instant therelative movement between said light sensitive member and said opticalsystem equals the set width according to point size of the character tobe photographed.

2. The combination according to claim 1, wherein the adjustable unitmeasuring device comprises a relatively fixed photocell unit and a gridplate partaking of the line composing movement, said plate being formedwith a plurality of rows of differently spaced light transmittingmarkings, one row for each different point size, and adjustable undercontrol of the code signal to bring any selected row into alignment withthe light source of the photocell unit. j p

3. The combination according to claim 2, wherein the adjustment of thegrid plate is effected by a reversible electric motor and a commutatorwhich controls the extent and direction of adjustment of said plate.

4. The combination according to claim 3, wherein the code signalresponsive means comprises electric circuitry which is conditioned bythe code signal and which acts through the reversible motor in effectingthe required adjustment of the grid plate.

5. The combination according to claim 4, wherein the code signalresponsive means also comprises electric circuitry which is conditionedby the code signal and which varies the adjustment of the lens assemblyaccording to the point size represented by the signal.

6. The combination according to claim 5, wherein the adjustable pointsize changing lens assembly comprises two relatively adjustable lenses,and wherein the reversible motor which effects the required adjustmentof the grid plate also effects the corresponding adjustment of one ofsaid lenses.

7. The combination according to claim 6, wherein the rows of lighttransmitting markings on the grid plate are variably spaced apartaccording to the variable adjustments of the lens adjusted by the samemotor.

8. In a coded tape operated phototypographical machine equipped with anoptical system which includes a point size changing lens assemblycomprising two relatively adjustable lenses for reproducing typecharacters on a light sensitive member of dilferent predetermined pointsizes, the combination of means for adjusting one of said point sizelenses, separate means for adjusting the other of said lenses, and meansresponsive to a code signal on the operating tape for controlling theoperation of the two lens adjusting means to position said lenses inproper relation to each other according to the point size of thecharacters to be reproduced on said member, the adjusting means for eachlens including a reversible electric motor, and a commutator whichcontrols the extent and direction of adjustment of the correspondinglens.

9. The combination according to claim 8, wherein the code signalresponsive means comprises electric circuitry which is conditioned bythe code signal and which acts through the commutators in elfecting therequired adjustment of the two lenses.

10. In a coded tape operated phototypographical machine equipped with afont plate presenting an array of transparent type characters of a givenpoint size and which vary in set widths on a unit basis, a lamppositioned adjacent said plate and adapted when flashed to project lightthrough a selected character to an optical system which includes anadjustable point size changing lens assembly for photographing saidselected character on a light sensitive member of a differentpredetermined point size, means for producing a continuous relativemovement between the light sensitive member and said optical system, anda unit measuring device adapted to flash said lamp the instant therelative movement between the light sensitive member and the opticalsystem equals the set width of said character, the combination of meansresponsive to a code signal on the operating tape for varying the speedof the relative movement'between the light sensitive memberand saidoptical system so that the time required to flash said lamp is the sameregardless of the point size of the character photographed.

11. The combination according to claim 10, wherein the means forproducing a continuous relative movement between the light sensitivemember and the optical system includes a variable speed electric motor.

12. The combination according to claim 11, wherein the code signalresponsive means comprises electric circuitry which is conditioned bythe code signal and which varies the speed of the electric motoraccording to the point size of the character photographed.

13. In a coded tape operated phototypographical machine equipped with afont plate presenting an array of transparent type characters of a givenpoint size and which vary in set widths on a unit basis, a lamppositioned adjacent said plate and adapted when flashed to project lightthrough a selected character to an optical system which includes anadjustable point size changing lens assembly for photographing saidselected character on a light sensitive member of a differentpredetermined point size, means for producing relative movement betweenthe light sensitive member and said optical system, and a unit measuringdevice adapted to flash said lamp the instant the relative movementbetween the light sensitive members and the optical system equals theset width of said character, the combination of means responsive to acode signal on the operating tape for adjusting said lens assemblyaccording to the point size of the selected character to bephotographed, and means also responsive to said code signal for varyingthe intensity of the lamp so that said light sensitive member will besubject to the same amount of light regardless of the point size of thephotographed character.

14. The combination according to claim 13, wherein the code signalresponsive means for the lamp comprises electric circuitry which isconditioned by the code signal and which acts upon the lamp to vary thelight intensity according to the point size of the character to bephotographed.

15. In a coded tape operated phototoypographical machine equipped with afont plate presenting an array of transparent type characters of a givenpoint size and which vary in set widths on a unit basis, a lamppositioned adjacent said plate and adapted when flashed to project lightthrough a selected character to an optical system which includes anadjustable point size changing lens assembly for photographing saidselected character on a light sensitive member of a differentpredetermined point size, means for producing relative movement betweenthe light sensitive member and said optical system for line composition,and an adjustable unit measuring device adapted to flash said lamp theinstant the relative movement between the light sensitive member and theoptical system equals the set width of said character, the combinationof means responsive to the code signal on the operating tape for (1)adjusting said lens assembly according to the point size of thecharacter to be photographed, (2) adjusting said unit measuring deviceto flash said lamp the instant the relative movement between the lightsensitive member and said optical system equals the set width accordingto point size of the character to be photographed, and (3) varying thespeed of the relative movement between the light sensitive member andsaid optical system so that the time required to flash said lamp is thesame regardless of the point size of the character to be photographed.

16. In a coded tape operated phototypographical machine equipped with afont plate presenting an array of transparent type characters of a givenpoint size and which vary in set widths on a unit basis, a lamppositioned adjacent said plate and adapted when flashed to project lightthrough a selected character to an optical system which includes anadjustable point size changing lens assembly for photographing saidselected character on a light sensitive member of a differentpredetermined point size, means for producing relative movement betweenthe light sensimeagre tive memberand said optical system for linecomposition, and an adjustable unit measuring device adap t'd 'to' flashsaid lamp the instant'the relative movement between the light sensitivemember and the optical system equals the set width of said character,the combi nation'of means responsive to the code signal on'theopera-ting tape for (1) adjusting said lens assembly according to thepoint size of the character to be photographed, (2 adjusting said unitmeasuring device to flash said lamp'the instant'the relative movementbetween the light sensitive"mem ber and said optical system equals theset'width according to point size of the character to be photographed,(3) varying the speed of the relative'movemen't between the lightsensitive member and said optical system so that the time required toflash said lamp is the same regardless of the 15 1,732,049

12 point size of the character to'be'photographed, and (4) varying theintensity of the lamp so" that said light sensitive member will besubject to the same amount of light regardless of the point size of thephotographed character. 17. The combination according to claim 16wherein the codesignal responsive means comprisselectriccircuitry whichis conditioned by the code signal and which 'acts throughelectriccircuitry in controlling the function of the various elements,accordingto the point sizerepresented by the signal References Cited inthe iile of this pa'tent NIT D STATES PATENTS Hunter Oct.l5, 1929

